8/05/2009 @ 6:00PM

Beaming Up Holograms

“Help me, Obi-wan Kenobi; you’re my only hope,” beseeches a three-dimensional image of Princess Leia, effortlessly projected by the droid R2-D2 in a well-known scene from the first Star Wars movie. In reality, generating such lifelike holograms for communication on the fly has remained elusive–until now.

Paul Debevec and several researchers at the University of Southern California’s Institute for Creative Technologies have built a teleconferencing system that captures a person’s face and head and instantaneously displays it as a 3-D image. Surprisingly, much of Debevec’s system consists of consumer-grade parts: a standard video camera, an off-the-shelf graphics card and an Internet connection.

What makes it work are clever algorithms that efficiently calculate the 3-D information, a rapidly spinning mirror and a couple of tricked-out video projectors hot-wired to display 8,640 frames per second. Normal projectors display 60 frames per second.

A video camera captures an image of the user’s face, while a projector casts a set of blurry lines that scan the face for depth and texture. Two projectors trained on a mirror spinning at 900rpm inside a Plexiglas box create a somewhat ethereal but realistic-looking head.

Debevec, 38, the institute’s associate director for graphics research, is a Star Wars fan and a graphics guru. Previous systems he’s developed have been used to create digital models of actors in movies such as The Curious Case of Benjamin Button and Spider-Man 2.

The 3-D project was three years in the making; help also came from usc’s film school and Fakespace Labs, a nasa spinout company. It has generated considerable interest from the U.S. Army, which provided an undisclosed amount of funding. Debevec has also been in talks with teleconferencing companies and theme parks about commercial applications.

The day is not far off, says Debevec, when eager consumers may use the technology to have their own Princess Leia moment. “Except for projecting onto thin air, we can do everything Star Wars can,” he says.